diff mbox series

gas: avoid UB on signed multiplication in resolve_symbol_value()

Message ID 59c46287-cfce-444e-a16a-9d01d54026af@suse.com
State New
Headers
Series gas: avoid UB on signed multiplication in resolve_symbol_value() |

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Commit Message

Jan Beulich Dec. 9, 2024, 9:10 a.m. UTC 
  Commit 487b0ff02dda ("ubsan: signed integer multiply overflow") touched
only one of the two affected places (the 3rd, resolve_expression(), is
already using valueT type local variables).
---
Of course it's quite bad that we have three places evaluating
expressions, all doing things a little differently. Question is whether
unifying things is (a) practical and (b) not going to cause regressions.
diff mbox series

Patch

--- a/gas/symbols.c
+++ b/gas/symbols.c
@@ -1721,7 +1721,8 @@  resolve_symbol_value (symbolS *symp)
 
 	  switch (symp->x->value.X_op)
 	    {
-	    case O_multiply:		left *= right; break;
+	    /* See expr() for reasons of the use of valueT casts here.  */
+	    case O_multiply:		left *= (valueT) right; break;
 	    case O_divide:		left /= right; break;
 	    case O_modulus:		left %= right; break;
 	    case O_left_shift: